PT-2026-66724 · Red Hat · Red Hat Build Of Keycloak+3

CVE-2026-18208 · Published 2026-07-31 · Updated 2026-07-31

Mitre

CVSS v3.1

6.5

Medium

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

A flaw was found in the OIDC token introspection endpoint of the keycloak-services component. Keycloak is an open-source identity and access management solution used to secure modern applications and services. The issue occurs when a confidential client, configured to receive signed JWT introspection responses, attempts to introspect a token issued for a different audience. Although the endpoint correctly identifies the token as inactive for that client, it still returns the full set of token claims within a signed JWT field. This allows an unauthorized client to bypass audience-based restrictions and access sensitive information contained in the token.

Fix

Missing Authorization

Weakness Enumeration

CWE-862

Related Identifiers

CVE-2026-18208

Affected Products

Red Hat Build Of Keycloak

Red Hat Data Grid 8

Red Hat Jboss Enterprise Application Platform Expansion Pack

Red Hat Single Sign-On 7

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-18208 · Security Note
• https://access.redhat.com/security/cve/CVE-2026-18208 · Note
• https://bugzilla.redhat.com/show_bug.cgi?id=2508304 · Note